Integrated Process to Co-Produce Trans-1-Chloro-3,3,3-Trifluoropropene, Trans-1,3,3,3-Tetrafluoropropene, and 1,1,1,3,3-Pentafluoropropane

ABSTRACT

Disclosed is an integrated process to co-produce trans-1-chloro-3,3,3-trifluoro-propene (1233zd(E)), trans-1,3,3,3-tetrafluoropropene (1234ze(E)), and 1,1,1,3,3-pentafluoropropane (245fa). Overall the co-production is a three-step process. The chemistry involves the steps of:
         (1) the reaction of 240fa with anhydrous HF in excess in a liquid-phase catalyzed reactor in such a way as to co-produce primarily 1233zd(E) and 244fa (plus byproduct HCl);   (2) the 244fa stream can then be used to directly produce any of the three desired products;   (3a) the 244fa stream can be dehydrochlorinated to produce the desired second product 1234ze(E); and/or   (3b) the 244fa stream can be dehydrofluorinated to produce 1233zd(E) if more of that product is desired; and/or   (3c) the 244fa stream can be further fluorinated to form 245fa.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims domestic priority from commonly owned,copending, U.S. Provisional Patent Application Ser. No. 61/434,002,filed Jan. 19, 2011, the disclosure of which is hereby incorporatedherein by reference.

BACKGROUND OF THE INVENTION

The use of chlorofluorocarbons or hydrochlorofluorocarbons asfoam-blowing agents has been banned due to concerns that their releasedamages the ozone layer. More recently, foam-blowing (addition of avolatile material to a polymeric mixture to cause a bubbled matrix whichimparts insulation or cushioning value) has been accomplished throughuse of 1,1,1,3,3-pentafluoropropane (245fa); however, concern has beenraised about the Global Warming Potential of this material.

Once candidate to eventually replace 245fa in these applications istrans-1-chloro-3,3,3-trifluoropropene (1233zd(E)). This material alsohas potential use as a solvent. See for example, U.S. Pat. No.6,844,475, which is hereby incorporated herein by reference.

A second candidate to replace 245fa for application in single componentfoam blowing applications is trans-1,3,3,3-tetrafluoropropene(1234ze(E)). See for example U.S. Pat. Nos. 7,230,146 and 7,485,760, thedisclosures of which are hereby incorporated herein by reference.

A process used for the production of fluoropropanes and halopropenesincluding 1-chloro-3,3,3-trifluoropropene (1233zd),1,3,3,3-tetrafluoropropene (1234ze) and 245fa is taught in U.S. PatentPublication No. 2010/0168482 A1. These compounds are typically formed ina complex product mixture including other fluoropropanes and/orhalopropenes in addition to reactants and other byproducts.

One problem recognized in this art has been the continued need for aneconomical process for the continuous preparation of 1233zd(E) and1234ze(E). Compound 245fa will continue to be needed for some time as itis slowly phased out and new products are slowly phased in. Accordingly,the present invention provides an integrated process to co-produce thesethree compounds, starting from one common feed material, namely 240fa.

SUMMARY OF THE INVENTION

The present invention is directed to an integrated process to co-producetrans-1-chloro-3,3,3-trifluoro-propene (1233zd(E)),trans-1,3,3,3-tetrafluoropropene (1234ze(E)), and1,1,1,3,3-pentafluoropropane (245fa). Overall the co-production is athree-step process. The chemistry involves the steps of:

-   -   (1) the reaction of 240fa with anhydrous HF in excess in a        liquid-phase catalyzed reactor in such a way as to co-produce        primarily 1233zd(E) and 244fa (plus byproduct HCl);    -   (2) the 244fa stream can then be used to directly produce any of        the three desired products;    -   (3a) the 244fa stream can be dehydrochlorinated to produce the        desired second product 1234ze(E); and/or    -   (3b) the 244fa stream can be dehydrofluorinated to produce        1233zd(E) if more of that product is desired; and/or    -   (3c) the 244fa stream can be further fluorinated to form 245fa.

According to one embodiment of the present invention, 1233zd(E),1234ze(E), and 245fa can all be co-produced in an integrated processstarting with a single hydrochlorocarbon feed material, namely 240fa.One benefit of this process is that it avoids intimate contact of thecompounds 1233zd(E) and 245fa, which would otherwise form an azeotropiccomposition that makes it impossible to separate the components usingconventional separation techniques such as distillation.

The process has an economical advantage to produce 1234ze(E) over thosemethods previously disclosed in literature because it also uses theintermediate 1-chloro-1,3,3,3-tetrafluoropropane (244fa) as a precursorinstead of 245fa. These compounds can both be produced from the same240fa feed stock, but 245fa has an extra fluorine atom that is added tothe original feed stock—which must be removed as HF to produce1234ze(E). Thus, using 245fa to produce 1234ze (E) wastes one mole of HFper mole of 1234ze (E) produced. On the other hand, 1234ze(E) can beproduced from 244fa by removing the last remaining chlorine atom (in theform of HCl) from the original feed stock.

The preferred process of the present invention also has an advantage inthat it allows for great flexibility in producing different amounts ofeach compound by adjusting the operating conditions or concentrations ofreactants and/or catalyst in the first liquid phase reactor.

The preferred integrated manufacturing process is different from priorart because it also includes the ability to recycle unreacted startingmaterials to maximize raw material utilization and product yields. Italso provides the ability to isolate by-products that may be sold forcommercial value.

BRIEF DESCRIPTION OF THE DRAWING

The FIGURE illustrates the relative positions of the seven major unitoperations of a preferred manufacturing process of the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

It has now been found that 1234ze(E) and 245fa may be continuously andeconomically co-produced via an integrated manufacturing process whichstarts with a single chlorinated hydrocarbon, 240fa. One preferredembodiment of a fully integrated co-manufacturing process for making1233zd(E) and 1234ze(E) is described in detail below.

Overall the co-production is a three-step process. The chemistryinvolves:

-   -   (1) the reaction of 240fa with anhydrous HF in excess in a        liquid-phase catalyzed reactor in such a way as to co-produce        primarily 1233zd(E) and 244fa (plus byproduct HCl);    -   (2) the 244fa stream can then be used to directly produce any of        the three desired products;    -   (3a) the 244fa stream can be dehydrochlorinated to produce the        desired second product 1234ze(E); and/or    -   (3b) the 244fa stream can be dehydrofluorinated to produce        1233zd(E) if more of that product is desired; and/or    -   (3c) the 244fa stream can be further fluorinated to form 245fa.

Desired Reactions:

-   -   Step 1:

Step 2:

Step 3:

The manufacturing process preferably consists of the following sevenmajor unit operations:

-   (1) Liquid phase fluorination catalyst preparation (Titanium    tetrachloride);-   (2) Fluorination reaction (continuous or semi-batch mode) using HF    with simultaneous removal of byproduct HCl and the co-products    1233zd(E) and 244fa;-   (3) Separation and purification of byproduct HCl;-   (4) Separation of excess HF back to (2);-   (5) Purification of final product, 1233zd(E);-   (6) Dehydrochlorination of 244bb to 1234ze(E) (with recycle of HCl    to recovery); and-   (7) Purification of final product, 1233zd(E).    One embodiment of the relative positions of these operations is    shown in the FIGURE.

Liquid Phase Fluorination Catalyst Preparation, Reactor 1

The reaction uses a liquid phase catalyst of proper strength to achievethe desired reaction; preferentially it has been found that a catalystcomprised of titanium tetrachloride (liquid under ambient conditions)which has been partially or totally fluorinated by the action ofanhydrous HF, achieves the desired degree of conversion without formingundesired volatile byproducts. The catalyst fluorination is conducted byadding a specified amount of titanium tetrachloride to the agitated,temperature-controlled reactor vessel, and adding HF by a gradual flow.A moderate amount of HCl will be generated in the operation. Conditions:10° C. to 50° C. and at about 0 to 100 psig pressure. Additionalfluorination catalysts that can be used include (all are partially oftotally fluorinated by the action of anhydrous HF) SnCl₄, TaCl₅, SbCl₃,AlCl₃, SbCl₅, alone or in combination.

Reaction and Stripping Column, Reaction 1

One key to the reaction is the equipment arrangement. An agitated,temperature-controlled reactor for the contact of both feed materialswith the liquid catalyst and an integrated distillation column whichpermits the product to leave (along with byproduct HCl, traces of lightorganics, principally 1234ze(E+Z), and some anhydrous HF (AHF), whileretaining the bulk of the HF, plus under-fluorinated and dimerizedorganics, plus the catalyst is another key. Preferably the reactor isconstructed from materials which are resistant to the corrosive effectsof the HF and catalyst, such as Hastelloy-C, Inconel, Monel, Incoloy, orfluoropolymer-lined steel vessels. Such liquid-phase fluorinationreactors are well known in the art.

Once the catalyst has been prepared, the reaction can be initiatedimmediately. The flow of HF for the catalyst preparation need not bediscontinued. An additional amount of HF is added to the reactor to fillthe reactor to 20% to 90% of its volume while the reactor is heated to atemperature of 85° C. to 95° C. and agitated. Then the addition of the240fa can be started immediately to cause continuous reaction whilemaintaining the flow of HF at an amount sufficient to produce thedesired products plus an excess amount to account for losses due toazeotrope compositions of 1233zd(E)/HF and 244fa/HF that exit the top ofthe integrated distillation column. The reaction runs under HF richconditions to produce the reaction co-products, 1233zd(E) and 244fa.Proper temperature control of the coolant and sufficient reflux actionare necessary for the stripping column to be effective.

General operating conditions which have been found to work well for thereaction and stripping are: operating pressure of from 80 psig to 140psig maintained by a control valve on the exiting flow from the strippercolumn; reactor temperature of 85° C. to 115° C., primarily supplied bysteam flow into the reactor jacket; application of brine cooling to theheat exchanger on top of the stripper column to induce reflux;temperature in the center portion of the stripper about 10° C. to 40° C.below that in the reactor; additional heat input by superheating the HFvapor feed with high-pressure steam to 120° C. to 150° C.; feed rate ofHF to maintain reactor and stripper conditions.

Recycle of Underfluorinated Intermediates and HF

The stream exiting the stripper column (2) enters a recycle column. Herethe high boiling underfluorinated intermediates and some HF areseparated and returned to reactor (2) for further reaction. The crudemixture containing 1233zd/244fa, HF, and HCl is fed forward in theintegrated process.

Removal of HCl

The stream exiting the recycle column (3) is combined with otheradditional process streams that contain 1233zd/244fa/1234ze, HCl and HF(described below, see (7) and (11)). The HCl in this combined stream canthen be purified and collected for sale using a low-temperature HCldistillation column. High purity HCl is isolated and can be absorbed inde-ionized water as concentrated HCl for sale.

Separation and Recycle of Excess HF Back to (2)

The bottom stream from the HCl column (4) that contains a crude productmixture of 1233zd/244fa/1234ze and about 30 wt % HF is fed to a sulfuricextractor or a phase separator for removal of HF from this mixture. HFis either dissolved in the sulfuric acid or phase separated from theorganic mixture. HF is desorbed from the sulfuric acid/HF mixture bystripping distillation and recycled back to the reactor. The organicmixture either from the overhead of the sulfuric acid extractor mayrequire treatment (scrubbing or adsorption) to remove traces of HFbefore it is fed to the next unit operation (6).

Purification of Final Products 1233zd(E) and 1234ze(E)

Purification of final products 1233zd(E) and 1234ze(Z) consists of threecontinuously operating distillation columns. The first column is used toremove light ends (including 1234ze(E)) from the crude. The light endsfrom the first column are fed to a second column is which 1234ze(E) isisolated in the column overhead. It should be recognized that at somepoint a purge of light byproducts from this stream will also berequired. The third column takes the heavy ends from the first columnand produces product grade 1233zd(E) as an overhead product. The thirdcolumn bottoms fraction contain mostly 244fa and is combined with thebottoms of the second column. A portion of the combined stream (portionis dependant on the desired product split) is fed to a vapor phasereactor (7) and a portion is fed to a liquid phase fluorination reactor(8). It should be recognized that at some point a purge of heavybyproducts from this stream will also be required.

Dehydrohalogenation of 244fa to 1234ze(E) or 1233zd(E)

A portion of the combined streams from the bottom of the distillationcolumns in (6) is fed to one or more catalyzed vapor phase reactorswhere the 244fa is either (a) dehydrochlorinated to produce the desired1234ze(E) product and HCl and/or (b) dehydrofluorinated to produceadditional amounts of 1233zd(E) and HF.

Optionally, the reactor(s) contains both a dehydrochlorination anddehydrofluorination catalyst that produces both 1233zd(E) and 1234ze(E).The reactor effluent is recycled back to the HCl recovery column (4).Optionally, 245fa produced in (9) can also be recycled back to this stepfor dehydrofluorination to form 1234ze(E).

Liquid Phase Fluorination Catalyst Preparation, Reactor 2

The reaction uses a liquid phase fluorination catalyst of properstrength to achieve the desired reaction; preferentially it has beenfound that a catalyst comprised of antimony pentachloride (liquid underambient conditions) which has been partially or totally fluorinated bythe action of anhydrous HF achieves the desired degree of conversionwithout forming undesired byproducts. The catalyst fluorination isconducted by adding a specified amount of antimony pentachloride to anon-agitated, temperature-controlled reactor vessel, and adding HF by agradual flow. A moderate amount of HCl will be generated in theoperation. Conditions: reaction temperature, from 10° C. to 50° C. andfrom 0 psig to 100 psig pressure. Additional fluorination catalysts thatcan be used include in combination with antimony pentachloride (all arepartially of totally fluorinated by the action of anhydrous HF) TiCl₄,TaCl₅, SbCl₃.

Reaction and Stripping Column, Reaction 3

One key to the reaction is the equipment arrangement. A non-agitated,temperature-controlled reactor for the contact of both feed materialswith the liquid catalyst and an integrated distillation column whichpermits the desired 245fa product to leave, along with byproduct HCl andan amount of AHF greater than or equal to the amount needed to form anazeotrope with 245fa at the reaction pressure, while retaining the bulkof the HF, plus under-fluorinated and plus the catalyst is another key.Preferably the reactor is constructed from materials which are resistantto the corrosive effects of the HF and catalyst, such asfluoropolymer-lined steel vessels. Such liquid-phase fluorinationreactors are well known in the art. Once the catalyst has been prepared,the reaction can be initiated immediately upon heating to the desiredreaction temperature. The flow of HF for the catalyst preparation neednot be discontinued while the reactor is heated to a temperature of 85°C. to 95° C.

Preferably the HF feed is vaporized and superheated to provide the heatnecessary to maintain proper reactor operating temperatures. Then theaddition of the organic mixed feed (244fa/1234ze(Z)/1233zd(Z)/1233zd(E))can be started immediately to cause continuous reaction whilemaintaining the flow of HF at an amount sufficient to produce thedesired product plus an excess amount to account for losses due toazeotrope compositions of 245fa/HF that exit the top of the integrateddistillation column. The reaction runs under HF rich conditions toproduce the reaction product, 245fa. Proper temperature control of thecoolant and sufficient reflux action are necessary for the strippingcolumn to be effective.

General operating conditions which have been found to work well for thereaction and stripping are: operating pressure of 80 psig to 140 psigmaintained by a control valve on the exiting flow from the strippercolumn; reactor temperature of 85° C. to 115° C., primarily supplied bysuperheating the HF vapor feed with high-pressure steam to 120° C. to150° C. directly into the reaction mixture and steam flow into thereactor jacket; application of brine cooling to the heat exchanger ontop of the stripper column to induce reflux; temperature in the centerportion of the stripper about 10° C. to 40° C. below that in thereactor; additional heat input; feed rate of HF to maintain reactor andstripper conditions.

Acid Removal

The stream exiting the stripper column (9) enters an acid removal systemthat consists of a water absorption column followed by a causticabsorption column followed by a drier. Here HF and HCl are removed fromthe 245fa crude and then the crude is dried before purification througha product absorption column and crude product recycle column. Here thehigh boiling underfluorinated intermediates and some HF are separatedand returned to reactor (2) for further reaction. Crude 1233zd/244fa,HF, and HCl are fed forward in the integrated process.

Purification of Final Product 245fa

Purification of final product 245fa consists of two continuouslyoperating distillation columns. The first column is used to remove lightends, mainly 1234ze(E) from the 245fa and the second column is used toremove the heavier components, primarily 244fa. The light and heavy endsthat are removed from the top of the first column and bottom of thesecond column can both be recycled back to an earlier processing steplike (4) or (6).

Integrated Process—1233zd(E), 1234ze(E), and 245fa Co-Production withHCl and Sulfuric Acid HF Recovery

As shown in the FIGURE, the liquid phase reactor R1 is first chargedwith a fluorination catalyst selected from the group comprising TiCl₄,SnCl₄, TaCl₅, SbCl₃, AlCl₃, or SbCl₅, alone or in combination. TiCl₄ ismost preferred. HF is first added in an amount to totally fluorinate themetal chloride catalyst; e.g., when using TiCl₄ a greater than 4:1 moleratio of HF to catalyst is added. The catalyst preparation is done whilethe reactor is at 10° C. to 50° C. and at about 0 to 160 psig pressure.HCl is generated during catalyst preparation and can be vented out ofthe top of the catalyst stripper column CS-1 to control the reactorpressure at or below the intended operating pressure of the reactor.Preferably the reactor is constructed from materials which are resistantto the corrosive effects of the HF and catalyst, such as Hastelloy-C,Inconel, Monel, Incoloy, or fluoropolymer-lined steel vessels. Suchliquid-phase fluorination reactors are well known in the art.

Then additional HF is continuously added into R-1 via vaporizer, HX-1,until good agitation is achieved; thereafter, this feed can be left on.

The reactor contents are then heated to about 85° C. with agitation atwhich point the 240fa feed is started and the fluorination reactionbetween 240fa and HF is initiated. Continuous 240fa is fed directly intoreactor R-1 and not through heater HX-1. Optionally, 240fa is fed toreactor R-1 via HX-1.

The operating pressure of 60 psig to 160 psig (preferably 80 psig to 140psig) is maintained by a control valve on the exiting flow from thecatalyst stripper column CS-1 and the reactor temperature is kept in therange of 80° C. to 150° C., (preferably 85° C. to 115° C.) primarilysupplied by steam flow into the reactor jacket. A catalyst strippercolumn CS-1 is connected to the reactor, R-1, and serves the purpose ofknocking down and returning entrained catalyst, some HF, partiallyfluorinated intermediates, and some unreacted 240fa back to the reactorfor further reaction.

By adjusting the operating conditions or concentrations of reactantsand/or catalyst in the liquid phase fluorination reactor the reactioncan be made to produce different amounts of each desired co-products1233zd(E) and 244fa.

The stream exiting the top of catalyst stripper CS-1 consisting ofunreacted 240fa, partially fluorinated intermediates and by-products,overfluorinated by-products, HF, 1233zd(E+Z), 244fa, and HCl, thenenters recycle column D-1 where a stream consisting of mainly unreacted240fa, partially fluorinated intermediates, and the majority of the HFexits the bottom of the recycle column and is recycled back to theliquid phase fluorination reactor R-1 via vaporizer HX-1.

A stream consisting of mainly 1233zd(E), 244fa, HF, and HCl exits thetop of the recycle column and enters HCl column D-2. A stream consistingof mainly HCl by-product exits the top of the HCl column and is fed toan HCl recovery system. The recovered HCl by-product can be sold forprofit. The HCl column bottoms consisting mainly of HF, 1233zd(E), and244fa are then fed into an HF recovery system.

The HF recovery system starts with the crude 1233zd/244fa/HF streambeing vaporized in heat exchanger HX-2 and fed into HF absorption columnA-1. Here a liquid stream of 50% to 80% H₂SO₄ contacts the gaseous1233zd/HF stream and absorbs the majority of the HF. The stream exitingthe bottom of A-1 consists of HF/H₂SO₄/H₂O and is fed to heat exchangerHX-3 where it is heated to a temperature sufficient to flash themajority of the HF along with small amounts of H₂O and H₂SO₄. Thisstream is fed to HF recovery distillation column D-3. The liquidremaining after the HF is flashed off in HX-3 consisting mainly of H₂SO₄and H₂O (with 0% to 2% HF) is cooled in HX-4 and recycled back to HFabsorption column A-1.

The HF recovery column, D-3, bottoms stream consisting of mainly H₂SO₄and H₂O are recycled back to heat exchanger HX-3 Anhydrous HF isrecovered from the top of the HF recovery column, D-3, and is recycledback to the reactor R-1 via vaporizer are HX-1. The stream exiting thetop of HF absorption column A-1 consisting of mainly 1233zd(E) and 244fa(trace HF) is sent forward to a polishing system A-2 where the gaseousstream contacts a water or a caustic solution to remove trace HF and issubsequently dried with a desiccant. Acid free crude product exitingabsorber A-2 is sent to the first of three purification columns, D-4.

A stream exiting the top of the column D-4 consists mainly of 1234ze(E)and reaction bi-products that have boiling points lower than that of1233zd(E) is fed to1234ze(E) product recovery distillation column D-6.Product grade 1234ze(E) exits the top of distillation column D-6 toproduct storage. The 1234ze(E) product recovery column's bottoms streamconsists mainly of 1234ze(Z) and 1233zd(E) (possibly with a small amountof 245fa). This bottoms stream is combined with the bottoms stream fromthe1233zd(E) product recovery column D-5 (further described below).

This combined stream is then split into two separate streams A and B,the ratio of which is determined by the desired product distribution.Stream A is fed to vaporizer HX-5 and then to vapor phasedehydrohalogenation/isomerization reactor R-2. Any 245fa impurity willdehydrofluorinate in R-2 to produce the desired 1234ze(E) product. Inaddition, the 1234ze(Z) impurity will isomerize in R-2 to produce thedesired 1234ze(E) product. Stream B′s fate is described below.

The vapor phase dehydrochlorination catalysts employed in R-2 may bemetal halides, halogenated metal oxides, neutral (or zero oxidationstate) metal or metal alloy, or activated carbon in bulk or supportedform. When metal halides or metal oxides catalysts are used, preferablymono-, bi-, and tri-valent metal halides, oxide and theirmixtures/combinations, and more preferably mono-, and bi-valent metalhalides and their mixtures/combinations. Component metals include, butare not limited to, Cr³⁺, Fe³⁺, Mg²⁺, Ca²⁺, Ni²⁺, Zn²⁺, Pd²⁺, Li⁺, Na⁺,K⁻, and Cs⁺. Component halogens include, but are not limited to, F⁻,Cl⁻, Br⁻, and I⁻. Examples of useful mono- or bi-valent metal halideinclude, but are not limited to, LiF, NaF, KF, CsF, MgF₂, CaF₂, LiCl,NaCl, KCl, and CsCl. Halogenation treatments can include any of thoseknown in the prior art, particularly those that employ HF, F₂, HCl, Cl₂,HBr, Br₂, HI, and I₂ as the halogenation source.

When neutral, i.e., zero valent, metals, metal alloys and their mixturesare used. Useful metals include, but are not limited to, Pd, Pt, Rh, Fe,Co, Ni, Cu, Mo, Cr, Mn, and combinations of the foregoing as alloys ormixtures. The catalyst may be supported or unsupported. Useful examplesof metal alloys include, but are not limited to, SS 316, Monel 400,Incoloy 825, Inconel 625, Inconel 600, and Inconel 625.

Preferred catalysts include activated carbon, stainless steel (e.g., SS316), austenitic nickel-based alloys (e.g., Inconel 625), nickel,fluorinated 10% CsCl/MgO, and 10% CsCl/MgF₂. The reaction temperature ispreferably about 300° C. to 550° C. and the reaction pressure ispreferably from 0 psig to about 150 psig.

The reactor effluent from R-2 is recycled back to HCl recoverydistillation column, D-2 where the HCl is recovered.

Optionally, Stream A can be fed into a liquid phase stirred reactoralong with a caustic solution to dehydrohalogenate 244fa (major) and245fa (minor) and produce both desired products 1234ze(E) and 1233zd(E)as some of the 244fa will dehydrochlorinate and some willdehydrofluorinate.

The stream exiting the bottom of column D-4, consisting mainly of1233zd(E+Z), 244fa and heavier bi-products, is fed to 1233zd(E) productrecovery distillation column D-5. Product grade 1233zd(E) exits the topof distillation column D-5 to product storage. The 1233zd(E) productcolumn's bottoms stream consist mainly of 244fa, 1233zd(Z) and reactionbi-products with boiling points higher than that of 1233zd(E). Thisbottoms stream, after combination with the bottoms stream from 1234ze(E)product recovery column D-6, is then split into two separate streams Aand B, as described above. The 1233zd(Z) impurity will to some extentisomerize in R-2 to produce the desired 1233zd(E) product.

Liquid phase reactor R-3 is first charged with fluorination catalystalone or in combination from the group comprising SbCl₅, TiCl₄, SnCl₄,TaCl₅, SbCl₃, or AlCl₃, alone or in combination. SbCl₅ is mostpreferred. HF is first added in an amount to at least partiallyfluorinate the metal chloride catalyst; e.g., when using SbCl₅ a greaterthan 3:1 mole ratio of HF to catalyst is added. The catalyst preparationis done while the reactor is at 10° C. to 50° C. and at from 0 psig toabout 160 psig pressure.

HCl is generated during catalyst preparation and can be vented out ofthe top of the catalyst stripper column CS-1 to control the reactorpressure at or below the intended operating pressure of the reactor.Preferably the reactor is constructed from materials which are resistantto the corrosive effects of the HF and catalyst, such as afluoropolymer-lined steel vessels. Such liquid-phase fluorinationreactors are well known in the art.

Additional HF is continuously added into R-3 via vaporizer, HX-9, andthe reactor is heated until the desired reaction temperature of about90° C. is achieved, at which point Stream B is combined with the freshHF before HX-9 and then into R-3 where the fluorination reaction betweenHCFC-244fa (major), 1234ze(E) (minor), 1233zd(Z) (minor), and 1233zd(E)(minor) and HF is initiated.

The operating pressure of 60 psig to 160 psig (preferably 80 psig to 140psig) is maintained by a control valve on the exiting flow from thecatalyst stripper column CS-1 and the reactor temperature is kept in therange of 80° C. to 150° C., (preferably 85° C. to 115° C.) primarilysupplied by superheated HF feed and steam flow into the reactor jacket.A catalyst stripper column CS-1 is connected to the reactor, R-3, andserves the purpose of knocking down and returning entrained catalyst,some HF, partially fluorinated intermediates, and some unreacted 244fa,back to the reactor for further reaction.

The stream exiting the top of catalyst stripper CS-1 consisting mainlyof 245fa, HF, HCl, and unreacted starting organic materials then enterswater absorption column A-3 where most of the HF and HCl are removed.The aqueous stream exiting the bottom of the water absorber A-3 isneutralized and disposed of as waste. The stream exiting the top of thewater absorber column A-3 consisting of mainly 245fa and unreactedstarting organic materials (trace HF and HCl) is sent forward to apolishing system A-4 where the gaseous stream contacts a weak causticsolution to remove trace HF and HCl and is subsequently dried with adesiccant.

Acid free crude product exiting absorber A-4 is sent to the first of twopurification columns, D-7. A stream exiting the top of the column D-7consists mainly of 1234ze(E) and reaction bi-products that have boilingpoints lower than that of 245fa is recycled back to D-4 and the columnbottoms are fed to 245fa product recovery distillation column D-8.Product grade 245fa exits the top of distillation column D-8 to productstorage. 244fa and reaction bi-products that have boiling points higherthan that of 245fa are recycled back to D-4.

EXAMPLE 1

This example illustrates the continuous reaction where 240fa iscontinuously fed into a charge of titanium halide catalyst and HF.

A clean, empty 10-gallon jacketed, agitated reactor of Hastelloy Cconstruction was prepared. This reactor was connected to a two-inchdiameter vertical, PTFE-lined pipe containing packing material(stripper), which is in turn connected to an overhead heat exchanger.The heat exchanger was supplied with −40° C. brine circulation on theshell side. Vapors exiting this stripper were processed through ascrubber, in which temperature-controlled dilute potassium hydroxideaqueous solution was circulated. Vapors exiting this stripper werecollected in a weighed, chilled (−40° C.) cylinder, followed by asmaller cylinder in series chilled in a dry ice bath.

Initially about 1200 grams lbs of TiCl₄ was added as a catalyst,followed immediately by 28 lbs of HF. The reactor contents were heatedto about 85° C. while agitated and was at a pressure of 120 psig afterformation of HCl after catalyst fluorination. The HF feed to the reactorwas continued at a rate of 1 lb/hr after being vaporized through a steamheated exchanger. Then a continuous feed of 240fa was started at 1.0lb/hr. The reactor was kept at 85° C. to 87° C. and at a pressure of 120psig. Samples of the organic portion of the reactor effluent exiting thetop of the catstripper were analyzed using a GC. Results showed about a55 GC area % of 244fa and about 42 GC area % 1233zd(E). The reactor rancontinuously for 56 hours at these conditions with very consistentresults.

EXAMPLE 2

This example illustrates the semi-batch reaction where 240fa iscontinuously fed into a charge of titanium halide catalyst and HF.

The same reactor as in Example 1 was used. The reactor was charged with2600 grams of fresh TiCl₄ catalyst. The intent of the experiment wasactually to produce 1233zd(E) with high selectivity.

The process (reaction of 240fa+HF in the presence of TiCl₄ catalyst) waschanged from a completely batch process to a semi-continuous processwith the hopes of reducing the residence time of the G240 in the reactorand thereby reducing the formation of the over fluorinated species,244fa. The reactor was initially charged with 50 lbs of HF followed by13 lbs of G240 and. The reactor temperature was slowly increased andreaction was observed at about 80° C. to 85° C. The reaction was allowedto proceed for a couple of hours with the lighter componentscontinuously being taken overhead of the catstripper to the scrubber andproduct collection dry ice traps (DITs). The 240fa feed was then startedcontinuously and added into the vapor space of the reactor. The overheadtake-off system was modified so that a constant amount of material wastaken off the catstripper and the G240 feed rate was adjusted to matchthat rate. Several times during the production run the reactor wasshutdown to add more HF and started up again as before.

The selectivity of the reaction for producing 1233zd was surprisinglylow at 40% to 50%. The major by-product was the over fluorinated species244fa (50% to 55%). Running HF rich and a larger amount of catalystadversely affected the selectivity to 1233zd(E).

EXAMPLE 3

This example (called Run #3) illustrates the semi-batch reaction whereHF was continuously fed into a charge of titanium tetrachloride catalystand 240fa.

A clean, empty 10-gallon jacketed, agitated reactor of Hastelloy Cconstruction was prepared. This reactor was connected to a 2 inchdiameter vertical, PTFE-lined pipe containing packing material(stripper), which was in turn connected to an overhead heat exchanger.The heat exchanger was supplied with −40° C. brine circulation on theshell side. Vapors exiting this stripper were processed through ascrubber, in which temperature-controlled dilute potassium hydroxideaqueous solution was circulated. Vapors exiting this stripper werecollected in a weighed, chilled (−40° C.) cylinder referred to as theproduct collection cylinder, followed by a smaller cylinder in serieschilled in a dry ice bath.

For Run #3, 14 lbs of anhydrous HF was fed to assure catalystfluorination. Next, 1.5 lbs of TiCl₄ was added as a catalyst. HCl wasimmediately generated as observed by the build-up of pressure in thereactor. After the pressure was reduced by venting most of the HCl fromthe system, 50 lbs of 240fa was added. The reactor was heated. At about85° C. HCl started to be generated indicating that the fluorinationreaction was initiated. The system pressure was controlled at about 120psig. Additional HF was then fed continuously and product was collectedin the product collection cylinder until the 240fa was consumed. The GCanalysis of the crude material collected during the run was as follows:86.4% 1233zd(E); 5.5% G-244fa; 3.1% 1234ze(E); 1.5% 1233zd(Z); 1.1%1234ze(Z); 1.1% dimmer; and 0.2% trifluoropropyne.

EXAMPLE 4 244fa Dehydrohalogenation Over Metal Chloride Catalysts

In this example a series of mono-, bi-, and tri-valent metal chlorideswere used as dehydrohalogenation catalysts. 20 ml of catalyst was used.244fa was passed over each catalyst at a rate of 12 g/h at a temperatureof 350° C. As shown below in Table 1, all the mono- and bi-valent metalchloride catalysts provided a trans/cis (t/c)-1234ze selectivity higherthan 80% and a t/c-1233zd selectivity lower than 20%, indicating thesecatalysts are more active for 244fa dehydrochlorination than itsdehydrofluorination. In comparison, the mono-valent metal chloridecatalysts are more selective to form t/c-1234ze than bi-valent metalchloride ones.

A 244fa conversion higher than 90% was achieved over the followingcatalysts: 10.0 wt % LiCl/C, 10.0 wt % KCl/C, and 10.0 wt % MgCl₂/C. Onthe other hand, the tri-valent iron chloride catalyst exhibited at/c-1234ze selectivity of about 9% and a t/c-1233zd selectivity of about61%, which suggests that this catalyst is more active for 244fadehydrofluorination than its dehydrochlorination.

TABLE 1 244fa dehydrohalogenation over metal chloride catalysts at 350°C. Selectivity, % Conversion, t/c- Catalyst % 244fa t/c-1234ze 245fa1233zd Others 10.0 wt % LiCl/C 96.2 95.2 0.0 4.4 0.4 10.0 wt % KCl/C97.9 94.4 0.0 4.9 0.7 10.0 wt % MgC1₂/C 99.3 92.9 0.0 6.7 0.4 10.0 wt %NiC1₂/C 89.3 93.4 0.0 5.4 1.2 10.0 wt % CuC1₂/C 28.5 83.8 0.0 13.0 3.210.0 wt % ZnC1₂/C 29.4 80.8 1.0 17.0 1.2 10.0 wt % FeC1₃/C 66.8 9.4 24.361.4 4.9

EXAMPLE 5 244fa Dehydrohalogenation Over Alkaline Metal Chloride-DopedMgF₂ Catalysts

In this example a series of alkaline metal chloride-doped MgF₂ catalystsare used as dehydrohalogenation catalysts. 20 ml of catalyst is used.244fa is passed over each catalyst at a rate of 12 g/h at a temperatureof 350° C. As shown below in Table 2, all the alkaline metalchloride-doped MgF₂ catalysts provide a t/c-1234ze selectivity higherthan 90% and a t/c-1233zd selectivity lower than 5%, indicating thesecatalysts are much more active for 244fa dehydrochlorination than itsdehydrofluorination.

TABLE 2 Reactivity of alkaline metal chloride-doped MgF₂ catalystsduring 244fa dehydrohalogenation at 350° C. Selectivity, % Conversion,t/c- Catalyst % 244fa t/c-1234ze 245fa 1233zd others 10 wt % LiCl/MgF₂42.9 90.5 0.0 4.8 4.7 10 wt % KCl/MgF₂ 47.1 95.8 0.0 0.7 3.5 10 wt %CsCl/MgF₂ 51.4 97.0 0.0 0.0 3.0

EXAMPLE 6

This example illustrates the recovery of anhydrous HF from a mixture ofHF, 1233zd, and 244fa according to certain preferred embodiments of thepresent invention.

A mixture consisting of about 30 wt. % 1233zd(E), 40 wt. % 244fa, andabout 30 wt. % HF is vaporized and fed to the bottom of a packed columnat a feed rate of about 2.9 lbs per hour for about 4 hours. A stream ofabout 80 wt. % sulfuric acid (80/20 H₂SO₄/H₂O) with about 2% HFdissolved therein is fed continuously to the top of the same packedcolumn at a feed rate of about 5.6 lbs per hour during the same timeframe. A gaseous stream exiting the top of the column comprises1233zd(E) and 244fa with less than 1.0 wt. % HF therein. Theconcentration of HF in the sulfuric acid in the column bottoms increasesfrom 2.0 wt. % to about 15 wt. %.

The column bottoms containing sulfuric acid and about 15 wt. % HF iscollected and charged into a two gallon PTFE vessel. The mixture isheated to about 140° C. to vaporize and flash off HF product, which iscollected. The collected HF product contains about 6000 ppm water and500 ppm sulfur. The sulfuric acid contains about 500 ppm of TOC (totalorganic carbon).

The HF collected from flash distillation is distilled in a distillationcolumn and anhydrous HF is recovered. The recovered anhydrous HFcontains less than 50 ppm of sulfur impurities and lees than 100 ppmwater

EXAMPLE 7

This example demonstrates the purification of the acid free 1233zd(E)crude product. This is distillation column D-5 in FIG. 1. 92 lbs of acidfree 1233zd/244fa crude material produced in Example 2 was charged to abatch distillation column. The crude material contained about 94 GC area% and 6 GC area % impurities. The distillation column consisted of a 10gallon reboiler, two inch ID by ten feet long propack column, and ashell and tube condenser. The column had about 30 theoretical plates.The distillation column was equipped with temperature, pressure, anddifferential pressure transmitters. About 7 lbs of a lights cut wasrecovered which consisted of mainly 1234ze(Z+E), trifluoropropyne,245fa, and 1233zd(E). 82 lbs of 99.8+ GC area % 1233zd(E) werecollected. The reboiler residue amounting to about 3 lbs was mainly244fa, 1233zd(Z), 1233zd dimmer, and 1233zd(E). The recovery of 99.8+ GCarea % pure 1233zd(E) was 94.8%.

EXAMPLE 8

This example demonstrates the use of the recycle column. Arepresentative 1233zd(E) and 244fa liquid phase reactor effluent mixtureas determined in Example 2 is charged into a batch distillation column.The distillation column consists of a 10 gallon reboiler, two inch ID byten feet long propack column, and a shell and tube condenser with −40°C. coolant flow capability. The column has about 30 theoretical plates.The distillation column is equipped with temperature, pressure, anddifferential pressure transmitters. The distillation column feed mixtureis about 30 wt % HF, 37 wt % HCl and 33% 1233zd(E)/244fa crude. Thedistillation is run at a pressure of about 100 psig and a differentialpressure (delta P) of 15-20 inches of water.

Both the distillate and reboiler are sampled periodically and analyzedfor organic, HF, and HCl using gas and ion chromatography. Initially,HCl, organic, and HF are observed in both samples. As more material isremoved as distillate the concentration of the reboiler changes. First,the concentration of HCl decreases until it is undetectable. Thedistillation is allowed to proceed until the concentration of organic inthe reboiler sample decreases to only trace amounts as analyzed usinggas chromatography. At the conclusion of the distillation the materialremaining in the reboiler is essentially pure HF. The recovered HF(reboiler bottoms) is then used to demonstrate recycle of recovered HFback to the liquid phase fluorination reactor and works satisfactorily.

EXAMPLE 9

This example illustrates continuous distillation of the crude mixtureconsisting essentially of 1234ze(E), 1234ze(Z), and 245fa. Thedistillation column consisted of a 10 gallon reboiler, two inch ID byten feet long propack column, and a shell and tube condenser. The columnhad about 30 theoretical plates. The distillation column was equippedwith reboiler level indicator; temperature, pressure, and differentialpressure transmitters. The distillation was run at pressure of about 50psig and differential pressure of about 17 inches of H₂O in thecontinuous mode.

The feed consisting essentially of 1234ze(E), 1234ze(Z), 245fa, andsmall amount of impurities (see Table 3) was continuously feed via theinlet port at the bottom of the distillation column at the rate of about1.75 lb/hr. The distillate consisting essentially of 1234ze(E) and lightimpurity (see Table 3) was collected from the top of the condenser atthe rate of about 1.02 lb/hr. The stream consisting essentially of 245faand 1234ze(Z) (see Table 3) was continuously taken out from the bottomof reboiler at the rate of about 0.73 lb/hr in order to maintain thelevel of material in the reboiler at about 40%. The distillation was runcontinuously for about 1000 hours.

TABLE 3 Composition of 1234ze(E) distillation column streams3,3,3-trifluoropropyne 1234ze(E) 1234zc 1234ze(Z) 1233zd 245fa Wt. % Wt.% Wt. % Wt. % Wt. % Wt. % Feed 0.0263 58.1003 0.0253 11.3939 trace30.4542 composition Distillate 0.0497 99.9503 0.0000 — — — compositionBottoms — 0.0801 0.0604 27.1886 trace 72.6709 composition

EXAMPLES 10 AND 11

Examples for 244fa Dehydrohalogenation to t/c-1234ze and t/c-1233zd

In Example 10, fluorinated Cr₂O₃ was used as a dehydrohalogenationcatalyst. 20 ml of catalyst was charged into a ¾-inch Monel reactor.244fa feed was passed through the catalyst at a rate of 12 grams/hour ata temperature of 350° C.

As shown below in Table 4, the fluorinated Cr₂O₃ catalyst provided a1233zd selectivity of about 75% and a 1234ze selectivity of about 21%,indicating 1234ze and 1233zd can be co-produced from 244fadehydrohalogenation over this catalyst. All 244fa was converted duringthe reaction.

TABLE 4 244fa dehydrohalogenation over a fluorinated metal oxidecatalyst at 350° C. Selectivity (%) 244fa conv. t/c- Catalyst (%)t/c-1234ze 245fa 1233zd Others Fluorinated Cr₂O₃ 100.0 20.7 0.0 74.6 4.7

In Example 11, aluminum fluoride was used as dehydrohalogenationcatalyst. 20 ml of catalyst was charged into a ¾-inch Monel reactor.244fa feed was passed through each catalyst at a rate of 12 grams/hourat a temperature of 350° C.

As shown below in Table 5, the AlF₃ catalyst provided a 1233zdselectivity of about 77% and a 1234ze selectivity of about 22%,indicating 1234ze and 1233zd can be co-produced from 244fadehydrohalogenation over this catalyst. All 244fa was converted duringthe reaction.

TABLE 5 244fa dehydrohalogenation over a metal halide catalyst at 350°C. Selectivity (%) Catalyst 244fa conv. (%) t/c-1234ze 245fa t/c-1233zdothers AlF₃ 100.0 21.8 0.0 77.3 0.9

EXAMPLE 12

This example demonstrates the dehydrohalogenation of 244fa in a causticsolution to produce both 1234ze(E) and 1233zd(E). 539.5 grams of 9.3 wt% KOH solution and 135.4 grams of 90.0 GC area % pure 244fa were addedto a 1.0 liter stainless steel (SS) cylinder. The other major componentwas 1223xd which amounted to 9.2 GC area %. The cylinder was heated to75° C. to 80° C. and shaken for five (5) hours. A sample of the vaporspace showed the presence of 75.6 area % 1234ze trans isomer, 12.9 area% 1234ze cis isomer, 8.5 GC area % 244fa, and 0.8 GC area % 1223xd. Asample of the organic liquid phase showed 24.4 GC area % 1234ze(E), 12.9GC area % 1233zd(E) isomer, 44.2 GC area % 244fa, and 8.1 GC area %1223xd.

560.0 grams of aqueous solution was collected after the experiment whichamounts to a weight gain of 20.5 grams in the aqueous layer. Assumingthis weight gain is HCl that was produced during the dehydrochlorinationof 244fa it can be calculated that about a 60% conversion of 244fa to1234ze occurred during the reaction.

EXAMPLE 13

A continuous liquid phase fluorination of a mixed stream containing244fa, 1233zd(Z), 1233zd(E), and 1234ze(Z) is demonstrated. Thefluorination catalyst for the experiment is SbCl₅. 6500 grams of SbCl₅are contained in a PTFE-lined liquid phase reactor equipped with acatalyst stripper, two-inch ID (inside diameter) packed column and witha condenser whose function is to return entrained catalyst, some of theunreacted HF and some of the unreacted organic back to the reactor whenthe system is running in continuous reaction mode. The reactor is2.75-inch ID×36-inch L (length) and is not equipped with amixer/agitator. The reactor is heated to about 85° C. to 87° C. Thecatalyst is then activated by the addition of 1500 grams of HF followedby 1500 grams of Cl₂. HCl generated by the fluorination of the catalystraises the reaction system pressure to about 100 psig where it iscontrolled.

The continuous gaseous HF feed is started first. It is bubbled into theliquid catalyst through a dip tube at a rate of 1.9 lb/hr, and when 1.0lb of HF has been added, the mixed organic feed stream is introduced. Italso enters the liquid catalyst by way of a dip tube and consist ofabout 83% 244fa, 10% 1234ze(Z), 5% 1233zd(Z), and 2% 1233zd(E). Themixed organic is fed continuously at rate of 2.0 lb/hr. The mole ratioof HF to organic raw material is 7:1. The reaction temperature ismaintained at 90° C. to 95° C. and the pressure is maintained at 120psig. 245fa, unreacted organic, organic by-products, HCl, and unreactedHF exit the top of the catstripper column. The experiment is runcontinuously for over 500 hours and the average conversion of theorganic raw material is greater than 99.5% while the selectivity to245fa reaches 99.5%. Cl₂ (0.02 mole/mole organic) is continuously fedinto the reaction mixture on a periodic basis through a dip tube inorder to keep the catalyst active.

EXAMPLE 14

245fa crude material exiting a 50 gallon pilot plant fluorinationreaction system was contacted with water in an absorption column toremove HCl and HF. Only a trace amount of acid remained. This stream wasthen contacted by a dilute caustic stream in a second absorber removingthe remaining acid. The stream was then passed through a columncontaining X13 molecular sieves to remove any moisture that was added tothe stream during contact with water during the acid removal step.

EXAMPLE 15

The dried and acid free 245fa crude material from Example 13 was thendistilled continuously to greater than 99.95% purity using a series oftwo conventional distillation columns to remove most of the low and highboiling impurities.

As used herein, the singular forms “a”, “an” and “the” include pluralunless the context clearly dictates otherwise. Moreover, when an amount,concentration, or other value or parameter is given as either a range,preferred range, or a list of upper preferable values and lowerpreferable values, this is to be understood as specifically disclosingall ranges formed from any pair of any upper range limit or preferredvalue and any lower range limit or preferred value, regardless ofwhether ranges are separately disclosed. Where a range of numericalvalues is recited herein, unless otherwise stated, the range is intendedto include the endpoints thereof, and all integers and fractions withinthe range. It is not intended that the scope of the invention be limitedto the specific values recited when defining a range.

It should be understood that the foregoing description is onlyillustrative of the present invention. Various alternatives andmodifications can be devised by those skilled in the art withoutdeparting from the invention. Accordingly, the present invention isintended to embrace all such alternatives, modifications and variancesthat fall within the scope of the appended claims.

1. An integrated process to co-producetrans-1-chloro-3,3,3-trifluoropropene (1233zd(E)),trans-1,3,3,3-tetrafluoropropene (1234ze(E)), and1,1,1,3,3-pentafluoropropane (245fa) comprising the steps of: (1)reacting 240fa with HF in a liquid-phase catalyzed reactor so as toco-produce 1233zd(E) and 244fa, plus byproduct HCl; (2) further reactingthe 244fa product stream as follows: (3a) the 244fa stream isdehydrochlorinated to produce 1234ze(E); and/or (3b) the 244fa stream isdehydrofluorinated to produce 1233zd(E); and/or (3c) the 244fa stream isfurther fluorinated to produce 245fa.
 2. The process of claim 1, whereinthe 244fa stream is dehydrochlorinated to produce 1234ze(E).
 3. Theprocess of claim 1, wherein the 244fa stream is dehydrofluorinated toproduce 1233zd(E).
 4. The process of claim 1, wherein the 244fa streamis further fluorinated to produce 245fa.
 5. The process of claim 1,wherein the step (1) fluorination reaction is conducted in a continuousmode with simultaneous removal of the byproduct HCl and separation ofthe 1233zd(E) and 244fa.
 6. The process of claim 1, wherein the step (1)fluorination reaction is conducted in a batch mode with removal of thebyproduct HCl and separation of the 1233zd(E) and 244fa.
 7. The processof claim 1, wherein the liquid phase fluorination catalyst is selectedfrom the group consisting of TiCl₄, SnCl₄, TaCl₅, SbCl₃, AlCl₃, orSbCl₅, alone or in combination.
 8. The process of claim 1, wherein step(3b) is a vapor phase reaction using a dehydrofluorination catalyst. 9.The process of claim 8, wherein the dehydrofluorination catalyst isselected from the group consisting of fluorinated metal oxides, metalfluorides, and supported metal catalysts.
 10. The process of claim 8,wherein the dehydrofluorination catalyst is fluorinated Cr₂O₃.
 11. Theprocess of claim 1, further comprising one or more purification steps torecover the 1233zd(E), 245fa, and 1234ze(E) products.
 12. The process ofclaim 6, which further includes HCl recovery.
 13. The process of claim12, which further includes an HF recycle step.
 14. The process of claim13, which further includes recycle of unreacted 245fa.